An artificial chockstone is inserted into an exposed fissure in a rock face in order to facilitate the climbing of the rock face. The chockstone normally includes a loop hanging therefrom for receiving therein a length of rope which secures two or more climbers together. It is usual practice to utilize a rope, secured in slidable manner to the face being climbed, in order to prevent the fall of all climbers should one climber slip.
Numerous chockstones are utilized during the climbing of a rock face. The chockstones must be lightweight, therefore, in order that they may be carried by the climbers, particularly by the lead climber. The chockstones must be easily and quickly insertable into the fissures in order to not delay the climbers. Naturally, the chockstones, when inserted, must securely grasp the walls of the fissure in order to perform the intended function.
The chockstones must be quickly and easily removable in order to not delay the climbers during the ascent or descent. Removability of the chockstones is required in order to prevent permanent scarring of the rock face after numerous climbs. Removability of the chockstones prevents the rock face from becoming cluttered with chockstones.
Jardine, U.S. Pat. No. 4,184,657, discloses a climbing aid wherein two pair of cam members are connected to a support bar. The cam members are spring-loaded and cooperate with an operating bar for being displaced between an open and a closed position. Jardine discloses connecting each of the cams to the operating bar by means of wire sections. It can be seen that the climbing aid of Jardine must first be configured for being inserted into the fissure. Secondly, the operating bar must then be released in order to permit the cams to swing outwardly in order to engage the walls of the rock face. Removal of the climbing aid is equally complicated. Consequently, insertion and removable of the climbing aid of Jardine is rendered difficult because of the necessity of orienting the cam members by means of the operating bar.
Lowe, U.S. Pat. No. 3,877,679, discloses an anchor device for mountain climbers wherein a main body is pivotably connected to an orientation assembly. The main body is spring-loaded whereby the main body is urged into a cam position. Insertion of the anchor device requires that the main body be properly oriented prior to insertion in the fissure. Removal of the chockstone is complicated by the need to properly orient the main body prior to removal. In fact, removal of the Lowe chockstone, as well as the other prior art chockstones, may be difficult, if not impossible, if improperly inserted.
The disclosed invention provides a unique artificial chockstone or spring activated cam anchor which is easily and quickly inserted and secured into a fissure in the rock face. The cams are spring-loaded such that an engagement surface of the cam extends outwardly beyond the upper surface of the frame to which the cams are pivotably connected. A linkage mechanism interconnects the cams with an actuation assembly and the cams are free to independently pivot from an insertion position to a withdrawal position. Each of the cams has an arcuate slot which receives a pin of the actuation assembly and which permits independent rotation of the cams so that the chockstone may be inserted into a fissure having an irregular surface without the need to orient the cams prior to insertion. Removal of the chockstone is easily accomplished through utilization of the levered actuation mechanism which rotates the cams from the insertion position.